1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73

Heavy and moist soil conditions that are ideal for the Phytophthora spp. fungus to flourish, as well as
rootstock/cultivar incompatibility may be the main causes for such high mortality in this block at the
Pittstown site. The humid conditions of the Northeast have also caused Bacterial Spot on the leaves
and fruit to be a disease we need to be conscious of.

Summer pruning (post-harvest) was done in 1998 (throughout the month of July) as per the
established protocols. This practice was established to minimize the spread of bacterial diseases
(Bacterial Spot, Bacterial Canker) that would be more active during the dormant pruning period than
would be during the summer months. Also the slight re-growth that is attained after summer pruning
can produce a harvestable crop during the next growing season therefore increasing yields.

Yield Data has not yet been compiled for the 1999 growing season. All reports are based on
observations and preliminary data.

Preliminary observations indicate there is tremendous variation in tree performance and mortality with
various plant material utilized as apricot rootstocks.

NJPC 5 (PlumCot hybrid) is establishing itself as the superior stock in this trial as to yield efficiency
and survival. It does have a tendency to overcrop itself and produce small fruit. The dwarfing
tendency that this stock seems to posses may be associated with scion incompatibility.

Prunus armeniaca"Haggith" produced the largest average fruit size in 1999, with an average of 58
gm/fruit. Prunus armeniaca"Haralayne" had the overall best yields.


Usefulness of Findings:
A good understanding has been developed as to the compatibility between Apricot (Prunus
armeniaca
) and many of the other species within the same genus, as well as their susceptibility to
Phytophthora spp.

Work Planned for Next Year:

Due to such a high mortality rate, and the lack of future statistical integrity, the termination of this
project is being discussed.


1999 North Jersey Tree Fruit Annual Report

54